Hydraulic jack



Jan. 28, 1930.

J. 1.. MALONE 1,745,024

' HYDRAULIC JACK I Filed April 1929 2 Sheets-Sheet 1 \l I wvw Jan. 28, 1930.

.J. L. MALONE HYDRAULIC JACK 2 Sheets-Sheet Filed April 18. 1929 q/vdmeoom wot/mu Patented Jan. 28,1930

JOHN LAFAYETTE MALONE, OF JACKSON, TENNESSEE i HYDRAULIC JACK Application filed April 18,

The invention aims to provide a rather simple and inexpensive, yet a highly efficient and desirable hydraulic jack which may be manufactured and assembled with ease and readily disassembled whenever repairs or replacements are necessary.

With the foregoing and minor objects in View, the invention resides in the novel subj ect matter hereinafter described and claimed,

description being accomplished by reference to the accompanying drawings.

Fig. 1 is a central vertical longitudinal sectional view partly in elevation.

Fig. 2 is a side elevation illustrating a yoke attached to the cylinder block of the jack for use in assembling or disassembling any tight fitting parts such as piston rods and cross heads.

Fig. 3 is an end elevation partly broken away and in section and looking in the direction indicated by the arrow A of Fig. 2.

The drawings above briefly described illustrate the preferred form of construction and while such construction will be herein specifically explained, it is to be understood that Within the scope of the invention as claimed, variations may be made.

The numeral 4 denotes a one-piece cylinder block having a flat bottom 5 to rest on a supao port. One vertical side 6 of the block 4 is flat and is provided at its lower portion with an externally threaded boss 7. The lower portion of the block 4 is formed with a comparatively small horizontal bore 8 in which a bushing 9 is threaded, the upper portion of said block 4 being provided with a relatively large vertical bore 10 opening through its upper end, and a port 11 places the inner end of the bushing 9 in communication with the lower end of the bore 10. An appropri ate plug or piston 12 is slidable in the bore 10 and is provided at its inner end with-a cup-leather or the like 13 to prevent fluid leakage when fluid is forced into said bore 10 from the port 11 to elevate said plug or piston. The fluid is driven into the port 11 from the bushing 9 by a plunger hereinafter described, and a check valve 14 is provided in the inner end of said bushing to normallv prevent backfiow of the fluid.

1929. Serial No. 356,075.

A container 15 for oil or other fluid is provided with a flat vertical side wall 16 contacting with the side 6 of the cylinder block 4, said wall 16 being formed with an opening 17 in which the boss 7 is threaded, thereby simply yet securely fastening the container 15 to the cylinder block 4. The side wall of the container 15 opposite the wall 16, is formed with an opening 18' horizontally alinedwith the bushing 9, said wall bein also provided with an outstanding annular ange 19 around said opening 18. Within this flange is an annular packing 2O compressible by a ring nut 21. A hollow head 22 is swiveled by any desired means 23 around the flange 19, said head being formed with an opening 24 alined with the bushing 9 and the opening 18 and being provided also with a peripheral slot 25.

A ported fluid-forcing plunger 26 extends horizontally across the lower portion of the container 15, the inner end portion of said plunger being received in the bushing 9 while the outer portion of said plunger passes through the openings 18-24, leakage of fluid around said plunger through the opening 18 being prevented by the packing 20. Plunger 26 is provided with a check valve 27 which, when said plunger is moved outwardly, permits fluid from the container 15 to enter the bushing 9, said valve closing however when the plunger is inwardly forced, so that the fluid is driven through the valve 14 and the port 11 into the cylinder bore 10 to elevate the piston 12. The plunger 26 is reciprocated 5 by means of a lever 28 which passes through the slot 25 of the head 22, is fulcrumed at 29 to said head and is provided with a bifurcated inner end 30 whose furcations are received in lateral notches 31 in the plunger.

Extending longitudinally in the plunger 26 and having a threaded connection 32 therewith, is a rod 33 which when threaded inwardly will serve to open the valve 27. When this is done, abnormal inward movement of the plunger 26 causes the latter to open the valve 14. Hence, fluid from the bore 10 may return to the container 15, allowing the piston 12 to lower. Upon return of the fluid to the containe 15, air is vented from the upper portion of said container through an appropriate check valve 34. As the fluid is forced from said container into the cylinder bore however, air may enter the upper end of 5 said container through another check valve 35. As both of these valves are normally closed, they prevent foreign matter from entering the container.

Ordinarily the jack is used in the position 19 shown in Fig. 1 with the flat bottom 5 of the cylinder block 4 resting upon any appropriate supporting surface. When so positioned, the swiveled head 24 permits swinging of the lever 28 to the most advantageous position for operation and such operation serves to pump fluid (preferably oil) from the container 15 into the cylinder bore 10 to elevate the piston 12, performing the desired lifting operation. Whenever a weight is to be lowso ered by permitting piston 12 to descend, the valves 27 14 are opened in the manner above explained, permitting back-flow of the fluid from the bore 10 into the container 15.

- When using the jack for assembling or disassembling any tight-fitting machine parts, it is desirable to use an appropriate adjustable yoke 36 as seen in Figs. 2 and 3, and to permit attachment of the yoke arms to .the

cylinder block 4, the latter is provided with $0 integral downwardly facing hooks 37 at its opposite sides. Obviously, it is not essential that the jack be used in the sition shown in Figs. 1, 2 and 3 as it may e employed to advantage turned to a horizontal position so or to any necessary inclined position. For

purposes of definite explanation however, the

description has been given with the use of such terms as upper, bottom, vertical, horizontal, etc.

I claim 1. A hydraulic jack comprising a flat bottom cylinder block having a relatively large vertical bore opening through its upper end and a comparatively small horizontal cylinder bore opening through one of its vertical sides, said horizontal and vertical bores being in check-valved communication, a vertically elongated fluid container secured to said vertical side of said cylinder block and communicating with said horizontal bore, one vertical side wall of said container being provided with a packing-equipped opening alined with said horizontal bore, a ported fluid-forcing check-valved plunger extending horizontally across the lower end of said container and slidably received in said horizontal bore and said opening, the outer end of said plunger projecting beyond said container, a head of small size in comparison with said container, said head being swiveled upon said vertical side wall of the container for turning movement about said plunger, an operating lever for said plunger fulcrumed upon said head, and a piston slidable in said vertical bore.

61 2. A hydraulic jack comprising a cylinder block having a flat bottom and a flat vertical side, the latter being provided at its lower pggion with an integral externally threaded said block having a relatively large ver tical bore opening through its up or end and a comparatively small horizonta bore opening throu h the outer end of said boss, the two bores sin in check-valved communica tion, a vertica ly elongated fluid container having a flat vertical s1de wall lyin tightly against said flat side of said cylinder block and formed with an opening into which said boss is threaded,the opposite vertical side wall ofsaid container being providedwith an opening alined with said horizontal bore and with an integral outstanding flange around said opening, a ported fluid-forcing check-valved plunger extending horizontall across the lower end of said container an slidably received in said horizontal bore and said alined opening, packing means for this openin confine within said flange, a hollow hea swiveled around said'flange and having an opening in which the outer end of said plungor is received, said head being provided also with a peripheral opening, an operatin lever for said plunger fulcrumed u on sai head and passing through said perip eral opening, and a piston slidable in saidvertical bore.

8. A hydraulic jack comprising a cylinder block having a vertical cylinder bore and a horizontal cylinder bore in check-valved communication with each other, a iston slidable in thevertical bore, a lunger slidable in said horizontal bore for orcing fluid into said vertical bore, a container for the fluid handled by the plunger, said container being secured directly to said cylinder block, operatin means for said plunger mounted upon sald container, and hooks integral with opposite sides of said cylinder block for engagement with a yoke.

4. In a hydraulic jack, a cylinder block having a bore, a bushing sleeve threaded into said bore and removable therefrom, an inwardly opening check valve carried by and disposed within the inner end of said bushing sleeve, and a fluid forcing plunger slidable in the outer portion of said bushin sleeve.

In testimony whereof I have hereunto affixed my si ature.

J O N LAFAYETTE MALONE. 

